
30/09/2024
This is so cool.
My lovely Misty had melanoma and it has made me hesitant to have another grey horse. This research will help breeders make choices to reduce the likelihood of melanoma in offspring.
Recent scientific breakthroughs have shed light on the genetic mechanisms behind the greying process in horses and their connection to melanoma susceptibility.
The mutation is particularly common in some breeds, for instance Lipizzaner and Arabian horses.
The key to this phenomena lies in the Syntaxin 17 gene.
Researchers identified three variants of the gene:
G1: The wild type (this is the "normal" or original version of the gene which indicates that the horse will not go grey.)
G2: The variant has two copies of the duplicated sequence. The G2 variant is associated with a gradual/ slow greying process and has no apparent increase in melanoma risk.
G3: The variant has three copies of the duplicated sequence. The G3 variant leads to rapid greying and a significantly elevated risk of melanoma development.
A specific segment of this gene can be duplicated, and the number of these duplications directly influences both the rate of greying and the likelihood of a horse developing melanomas.
The more copies of this duplicated sequence a horse possesses, the more pronounced the greying process and the higher the melanoma risk.
Horses can carry between two and six copies of this sequence, depending on their genetic inheritance.
This discovery has profound implications for horse breeding, since through genetic screening, breeders can now employ tests to predict a horse's melanoma risk from an early age.
Using this knowledge, breeders can make strategic mating choices to influence greying rates and mitigate risks in offspring.
The study genotyped 1,400 horses and 78 breeds/populations and found the G3 variant, associated with rapid greying, is prevalent in 62 breeds, while the G2 variant, linked to slower greying, is found in only eight breeds.
This research could have far-reaching implications for understanding tumor development in horses and may pave the way for improved prevention and treatment strategies for equine melanomas.
Full details - https://www.nature.com/articles/s41467-024-51898-2